* building within a docker container using docker from host by mounting `docker.sock` inside the container * building within a privileged docker container (new instance of docker is running inside) * executing build within current environment

* [GitPython](https://github.com/gitpython-developers/GitPython/) * [docker-py](https://github.com/docker/docker-py). * [koji](https://github.com/projectatomic/atomic-reactor/blob/master/atomic_reactor/plugins/pre_koji.py) plugin requires `koji` package, which is not available on PyPI: you have to install it manually:```$ yum install koji```

## Usage

If you would like to build your images within build containers, you need to obtain images for those containers. We call them build images. Atomic Reactor is installed inside and used to take care of build itself.

You can either get the build image from Dockerhub or create it yourself.

### getting build image from Dockerhub

Just use

```bash$ docker pull slavek/atomic-reactor```

This will pull the `buildroot` image with the latest Atomic Reactor commits. Images with stable releases are available since version 1.3.3 and you can access them by using the version specifier as a tag, such as

Why is it so long? Okay, let's get through. First thing is that Atomic Reactor needs to install itself inside the build image. You can pick several sources for Atomic Reactor: your local copy, (this) official upstream repo, your forked repo or even distribution tarball. In the example above, we are using our locally cloned git repo (`--reactor-local-path ${PATH_TO_REACTOR_GIT}`).

You have to provide Dockerfile too. Luckily these are part of upstream repo (see folder [images](https://github.com/projectatomic/atomic-reactor/tree/master/images)). It's the first argument: `${PATH_TO_REACTOR_GIT}/images/dockerhost-builder`.

1. `--reactor-tarball-path` — Atomic Reactor needs to install itself into build image: this is how you specify where Atomic Reactor gets its own sources (when installed via RPM, Atomic Reactor provides itself packaged as tarball at `/usr/share/atomic-reactor/atomic-reactor.tar.gz`)2. first argument is path do _dockerfile_ — dockerfiles for both methods are available at `/usr/share/atomic-reactor/images/`, just pick one3. and finally, second argument names the build image

#### getting Atomic Reactor from distribution

Or you can build the image using docker and install Atomic Reactor directly from distribution:

Built image will be in the build container. Therefore this example doesn't make much sense. If you would like to access the built image, you should probably push it to your registry and build it like this:

Both of these examples use the `git` source provider (`atomic-reactor build git`), which gets the source code to put in the image from a git repo. There are also other providers: * `path` - uses source code from local path * `json` - accepts a path to build json file with all info needed for build

IP address `172.17.42.1` should be address of docker0 network interface. Update it if yours is different. Also, don't forget to start the registry.

Bear in mind that you shouldn't mix build methods: if you use _hostdocker_ method with build image for _privileged_ method, it won't work.